Note 3 - Property and Equipment, Net - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Jun. 30, 2020
Property and equipment, gross	$ 9,042		$ 9,036
Less: Accumulated depreciation and amortization	(7,299)		(7,294)
Total	1,743	$ 1,742	1,742
Land and Building [Member]
Property and equipment, gross	1,250		1,250
Leasehold Improvements [Member]
Property and equipment, gross	1,371		1,364
Machinery and Equipment [Member]
Property and equipment, gross	6,415		6,416
Transportation Equipment [Member]
Property and equipment, gross	$ 6		$ 6

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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